function [SwirlingStrength] = SwirlingStrength(Dx,Dy,Ux,Uy,VorticityZfluc)

[DxUx , DyUx] = gradient(Ux , Dx , Dy);
[DxUy , DyUy] = gradient(Uy , Dx , Dy);

[Lambda] = Eigenvalues_2x2(DxUx , DxUy , DyUx , DyUy);

SwirlingStrength = abs( imag(Lambda) ) .* VorticityZfluc ./ abs(VorticityZfluc);
              
end